[llvm] [NFC][MC][DecoderEmitter] Refactor code related to EncodingField (PR #156759)

[Sergei Barannikov via llvm-commits]

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@@ -1100,17 +1105,17 @@ void DecoderTableBuilder::emitBinaryParser(raw_ostream &OS, indent Indent,
     OS << ";\n";
   }
 
-  for (const EncodingField &EF : OpInfo) {
+  for (const auto &[Base, Width, Offset] : OpInfo.fields()) {
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s-barannikov wrote:

I was hoping that EncodingField could be made a class someday.

https://github.com/llvm/llvm-project/pull/156759